Ossicône
- Ossicône
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L'ossicône est un appendice osseux crânien original qui caractérise les giraffidés actuels ainsi que certains taxons fossiles. Il est différent des cornes des bovidés et des bois des cervidés.
L'ossicône est présent chez les girafes, les okapis mâles, les Sivatherium (éteint) ainsi que chez les Climacoceratidae tels que Climacoceras.
Contrairement aux cornes des bovidés et aux bois des cervidés, les ossicônes sont couverts en permanence par de la peau et des poils et leur croissance se fait depuis un cartilage situé à leur base. Les cornes sont des extrémités protubérantes de la peau formées de kératine et couvrant des chevilles osseuses s'accroissant en volume et par leur pointe. Les bois sont recouverts temporairement par un velours richement vascularisé et ont une croissance apicale.
Sources
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2010.
Contenu soumis à la licence CC-BY-SA. Source : Article Ossicône de Wikipédia en français (auteurs)
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Ossicônes de girafe réticulée.
